Beamforming transmissions provide efficient signal and data transmissions in wireless communication systems. A beamforming transmitter generally forms its transmissions into one or more transmit beams through an antenna array. On the other hand, a beamforming receiver can either receive directly or receive based on information about the transmit beams. The latter alternative can provide more efficient transmission and higher spectral efficiency at the cost of indication of a transmit beam. However, the beamforming transmitter may change the beams it transmits in different transmissions in accordance with channel conditions. Timely and accurate indication of the transmit beam or a radio resource of the transmission is therefore needed for the receiver to efficiently receive signals.